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Severe fever with thrombocytopaenia syndrome virus (SFTSV) and Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) can cause the hyperproduction of inflammatory cytokines, which have pathological effects in patient including severe or fatal cytokine storms. To characterize the effect of SFTSV and SARS-CoV-2 infection on the production of cytokines in SFTS and COVID-19 patients, we performed an analysis of cytokines in SFTS and COVID-19 patients and also investigated the role of IL-10 in vitro studies: LPS-induced THP-1-derived macrophages, SFTSV infection of THP-1 cells, and SARS-CoV-2 infection of THP-1 cells. In this study, we found that levels of both IL-10 and IL-6 were significantly elevated, the level of TGF-β was significantly decreased and IL-10 was elevated earlier than IL-6 in severe and critical COVID-19 and fatal SFTS patients, and inhibition of IL-10 signalling decreased the production of IL-6 and elevated that of TGF-β. Therefore, the hyperproduction of IL-10 and IL-6 and the low production of TGF-β have been linked to cytokine storm-induced mortality in fatal SFTS and severe and critically ill COVID-19 patients and that IL-10 can play an important role in the host immune response to severe and critical SARS-CoV-2 and fatal SFTSV infection.

Background Enterotoxigenic Bacteroides fragilis (ETBF) causes colitis and diarrhea, and is considered a candidate pathogen in inflammatory bowel diseases as well as colorectal cancers. These diseases are dependent on ETBF-secreted toxin (BFT). Dendritic cells (DCs) play an important role in directing the nature of adaptive immune responses to bacterial infection and heme oxygenase-1 (HO-1) is involved in the regulation of DC function. Aim To investigate the role of BFT in HO-1 expression in DCs. Methods Murine DCs were generated from specific pathogen-free C57BL/6 and Nrf2-/- knockout mice. DCs were exposed to BFT, after which HO-1 expression and the related signaling factor activation were measured by quantitative RT-PCR, EMSA, fluorescent microscopy, immunoblot, and ELISA. Results HO-1 expression was upregulated in DCs stimulated with BFT. Although BFT activated transcription factors such as NF-κB, AP-1, and Nrf2, activation of NF-κB and AP-1 was not involved in the induction of HO-1 expression in BFT-exposed DCs. Instead, upregulation of HO-1 expression was dependent on Nrf2 activation in DCs. Moreover, HO-1 expression via Nrf2 in DCs was regulated by mitogen-activated protein kinases such as ERK and p38. Furthermore, BFT enhanced the production of reactive oxygen species (ROS) and inhibition of ROS production resulted in a significant decrease of phospho-ERK, phospho-p38, Nrf2, and HO-1 expression. Conclusion These results suggest that signaling pathways involving ROS-mediated ERK and p38 mitogen-activated protein kinases-Nrf2 activation in DCs are required for HO-1 induction during exposure to ETBF-produced BFT.

The rapid urease test (RUT) is a major diagnostic tool for detectingA UV-visible spectrophotometer was selected as the colorimeter; experiments were conducted in three stages to objectively identify the color changes in the RUT kit.First, the urea broth solution showed an identifiable color change from yellow to red as the pH increased by 0.2. The largest transmittance difference detected using the UV-visible spectrophotometer was observed at a 590-nm wavelength. Second, the commercialized RUT kit also showed a gradual color change according to the pH change detected using the UV-visible spectrophotometer. Third, 13 cases of negative RUT results with a biopsy specimen and 16 of positive RUT results were collected. The transmittance detected using the UV-visible spectrophotometer showed a clear division between the positive and negative RUT groups; the largest difference was observed at a 559-nm wavelength. The lowest transmittance in the negative RUT group was 64, while the highest in the positive RUT group was 56, at the 559-nm wavelength. The UV-visible spectrophotometry reading showed a consistency of 92.7% compared with that of manual reading.A transmittance of 60 at a 559-nm wavelength detected using UV-visible spectrophotometer can be used as a cutoff value for interpreting RUT results; this will help develop an automatic RUT kit reader with a high accuracy.

Bacteroides fragilis enterotoxin (BFT) produced by enterotoxigenic B. fragilis (ETBF) causes colonic inflammation. BFT initially contacts intestinal epithelial cells (IECs) and affects the intestinal barrier. Although molecular components of the gut epithelial barrier such as metalloproteinase-7 (MMP-7) and syndecan-2 are known to be associated with inflammation, little has been reported about MMP-7 expression and syndecan-2 shedding in response to ETBF infection. This study explores the role of BFT in MMP-7 induction and syndecan-2 release in IECs. Stimulating IECs with BFT led to the induction of MMP-7 and the activation of transcription factors such as NF-κB and AP-1. MMP-7 upregulation was not affected by NF-κB, but it was related to AP-1 activation. In BFT-exposed IECs, syndecan-2 release was observed in a time- and concentration-dependent manner. MMP-7 suppression was associated with a reduction in syndecan-2 release. In addition, suppression of ERK, one of the mitogen-activated protein kinases (MAPKs), inhibited AP-1 activity and MMP-7 expression. Furthermore, the suppression of AP-1 and ERK activity was related to the attenuation of syndecan-2 release. These results suggest that a signaling cascade comprising ERK and AP-1 activation in IECs is involved in MMP-7 upregulation and syndecan-2 release during exposure to BFT.

Severe fever with thrombocytopenia syndrome (SFTS) is a new tick-borne viral disease, and most SFTS virus (SFTSV) infections occur via bites from the tick Haemaphysalis longicornis; however, SFTSV transmission can also occur through close contact with an infected patient. SFTS is characterized by acute high fever, thrombocytopenia, leukopenia, elevated serum hepatic enzyme levels, gastrointestinal symptoms, and multiorgan failure and has a 16.2 to 30% mortality rate. In this study, we found that age, dyspnea rates, aspartate aminotransferase (AST), alanine aminotransferase (ALT), lactate dehydrogenase, multiorgan dysfunction score (MODS), viral load, IL-6 levels, and IL-10 levels were higher in patients with fatal disease than in patients with nonfatal disease during the initial clinical course of SFTS. In addition, we found that IL-6 and IL-10 levels, rather than viral load and neutralizing antibody titers, in patients with an SFTSV infection strongly correlated with outcomes (for severe disease with an ultimate outcome of recovery or death).

Severe fever with thrombocytopenia syndrome (SFTS), a newly emerging tick-borne viral disease, has been detected in Asia since 2009, and person-to-person transmission is possible. SFTS is characterized by atypical signs, including mild to severe febrile illness similar to that associated with hemorrhagic fever, with 16.2 to 30% mortality. We found that the titers of neutralizing antibodies, play an important role in protective immunity, to SFTS virus (SFTSV) in survivors and healthy residents who lived in endemic areas and who were positive for SFTSV IgG, were higher than those in non-survivor patients. Moreover, the titers were maintained in surviving patients and healthy residents but not in non-surviving patients in South Korea.

Enterotoxigenic Bacteroides fragilis is a causative agent of colitis and secrets enterotoxin (BFT), leading to the disease. Sulfiredoxin (Srx)-1 serves to protect from oxidative damages. Although BFT can generate reactive oxygen species in intestinal epithelial cells (IECs), no Srx-1 expression has been reported in ETBF infection. In this study, we explored the effects of ETBF-produced BFT on Srx-1 induction in IECs. Treatment of IECs with BFT resulted in increased expression of Srx-1 in a time-dependent manner. BFT treatment also activated transcriptional signals including Nrf2, AP-1 and NF-&kappa, B, and the Srx-1 induction was dependent on the activation of Nrf2 signals. Nrf2 activation was assessed using immunoblot and Nrf2-DNA binding activity and the specificity was confirmed by supershift and competition assays. Suppression of NF-&kappa, B or AP-1 signals did not affect the upregulation of Srx-1 expression. Nrf2-dependent Srx-1 expression was associated with the activation of p38 mitogen-activated protein kinases (MAPKs) in IECs. Furthermore, suppression of Srx-1 significantly enhanced apoptosis while overexpression of Srx-1 significantly attenuated apoptosis during exposure to BFT. These results imply that a signaling cascade involving p38 and Nrf2 is essential for Srx-1 upregulation in IECs stimulated with BFT. Following this upregulation, Srx-1 may control the apoptosis in BFT-exposed IECs.

Background: The increasing prevalence of antimicrobial resistance, together with the lack of novel treatment options, negatively affects successful eradication of Helicobacter pylori. The aim of this study was to investigate genetic mutations in the 23S rRNA genes, which is associated with clarithromycin resistance, and to determine the clinical impact of genotype on phenotypic antimicrobial resistance. Methods: A total of 46 H. pylori strains were obtained from 13 patients, before and after unsuccessful eradication with clarithromycin-based triple therapy. The phenotypic resistance of each H. pylori strain was determined by minimum inhibitory concentration against clarithromycin using the serial two-fold agar dilution method. The genomic sequences of 23S rRNA genes were identified through next-generation sequencing, and nucleotide variants were determined based on comparison with genome sequences of the reference strain H. pylori 26695. Results: Clarithromycin resistance was found in 9 of 13 subjects before treatment and all subjects after unsuccessful eradication. Whole-genome sequencing of the 23S rRNA genes detected 42 mutations on 40 nonidentical loci, including 2147A>G (formerly 2143A>G) and 2146A>G (formerly 2142A>G). All strains with clarithromycin-resistant phenotype had either 2147A>G or 2146A>G mutation. When comparing genotype and phenotype for clarithromycin resistance, there was a significant association between 2147A>G mutation and clarithromycin-resistant phenotype. Conclusions: All clarithromycin-resistant strains had either 2146A>G or 2147A>G mutation, suggesting that tests targeting these two mutations may be enough for the prediction of clarithromycin resistance in this population.

Purpose:Time-to-event data of hazard ratios were used to generate a forest plot of all-cause mortality on extracorporeal membrane oxygenation (ECMO) in both overall and individual indications of cardiopulmonary disease in adults. Materials and Methods:A systemic search was conducted in PubMed from 1975 to 2018. Among 4,121 articles, a total of 34 clinical reports comprising 20,610patients (1,631 of the patients who underwent ECMO and 18,979 of the patients who did not undergo ECMO) met the inclusion criteria. Results:The pooled hazard ratio of 1.2828 (95% confidence interval: 0.9649, 1.7054) suggests that the ECMO group was not significantly associated with a reduction in mortality compared with the no-ECMO group in the overall ECMO indications. The results of subgroup analyses showed a significantly improved patient survival in respiratory failure with 0.6308 (0.5037, 0.7900), and a worse patient survival after lung transplantation with 2.0600 (1.6987, 2.4981), in bridging to heart transplantation with 1.4212 (1.0309, 1.9592), and after heart transplantation with 5.6365 (1.7569, 18.0827). Conclusions:Most of the included studies are retrospective, which diminishes the significance of the findings due to a higher risk of selection bias, which was exemplified by the allocation of ECMO based on the patients’ severity condition.

Rationale A hemodynamic relationship of pulmonary artery pressure (PAP) to pulmonary acceleration time (PAcT) has not yet been explicitly presented. Objective We employed a logistic-based systolic model with a subtle modification for pulmonary circulation and provided a logical ground for the relationship between systolic PAP and PAcT using transthoracic echocardiography. Additionally, the logistic-based PAP estimation equation was deduced from the model to relate systolic PAP and PAcT. Methods and results This equation was statistically tested in comparison to existing PAP estimation equations. Results showed that the logistic-based PAP estimation equation was at least as accurate as previous equations with respect to previously published mean PAP versus PAcT values. After the subtle pulmonary modification of the model, the pulmonary blood flow velocity and pressure not only well reflected the underlying pulmonary circulation physiology, but could also be presented in harmony with systemic circulation physiology. Conclusions A future clinical study with actual systolic PAP versus PAcT measurements is needed to test the application of the logistic-based PAP estimation equation.

Background and Aim rdxA and frxA mutations and enhancement of efflux pump have been suggested as the cause of metronidazole resistance in Helicobacter pylori. This study was performed to investigate the resistance mechanisms related to clinical eradication outcome, and to examine direct involvement of hefA in metronidazole-resistant isolates with intact rdxA and frxA. Methods A total of 53 H. pylori-positive patients who were treated with metronidazole-containing sequential or quadruple therapy from 2011 to 2015 were enrolled. The metronidazole susceptibility of H. pylori isolates was examined by agar dilution test. Mutations in rdxA and frxA, were analyzed with DNA sequencing, and impact of hefA on metronidazole resistance was examined with qRT-PCR, knockout and genetic complementation test for hefA. Results Seven mutation types of rdxA and/or frxA were found in H. pylori isolated from non-eradicated subjects. rdxA mutation was associated with eradication failure (P = 0.002), and nonsense mutation in rdxA reduced eradication efficacy (P = 0.009). hefA expression was significantly higher in resistant isolates (P < 0.001), especially in rdxA(-)frxA(-) as compared to rdxA(+)frxA(+) (P = 0.027). Resistant isolates with no mutation in rdxA and frxA became susceptible after hefA knockout. Genetic complementation for hefA recovered metronidazole resistance in all of three hefA knockout mutants. Conclusions These results suggest that rdxA mutations play a critical role in metronidazole resistance as well as the outcomes of eradication therapy. In addition, hefA seems to be directly involved in metronidazole resistance, which explains the resistance in clinical isolates with intact rdxA and frxA.

Purpose:Time-to-event data of hazard ratios were used to generate a forest plot of mortality on extracorporeal membrane oxygenation (ECMO) in respiratory failure in adults. Materials and Methods:A systemic search was conducted in PubMed from 1975 to 2018. Among 4,121 articles, a total of 5 clinical reports comprising 1,014patients (333 of the patients who underwent ECMO and 681 of the patients who did not undergo ECMO) met the inclusion criteria. Results:The pooled hazard ratio of 0.64 (95% confidence interval (CI): 0.54, 0.76) suggests that the ECMO group comprising both veno-arterial (VA) type and a majority of veno-venous (VV) type was significantly associated with a reduction in mortality compared with the non-ECMO group in respiratory failure. The results of VV-ECMO alone also showed significantly improved patient survival of respiratory failure with the hazard ratio of 0.67 (0.56, 0.81). Conclusions:The results of the ECMO group with VV and VA types, or the VV type alone revealed a reduction in mortality for patients with respiratory failure based on time-to-event data.Future investigation of the efficacy of VA-ECMO alone in respiratory failure may be more enlightening.

The Bacteroides fragilis enterotoxin (BFT), a virulence factor of enterotoxigenic B. fragilis (ETBF), interacts with intestinal epithelial cells and can provoke signals that induce mucosal inflammation. Although β-catenin signaling is reported to be associated with inflammatory responses and BFT is known to cleave E-cadherin linked with β-catenin, little is known about the β-catenin-mediated regulation of inflammation in ETBF infection. This study was conducted to investigate the role of β-catenin as a cellular signaling intermediate in the induction of proinflammatory responses to stimulation of intestinal epithelial cells with BFT. Expression of β-catenin in intestinal epithelial cells was reduced relatively early after stimulation with BFT and then recovered to normal levels relatively late after stimulation. In contrast, phosphorylation of β-catenin in BFT-exposed cells occurred at high levels early in stimulation and decreased as time passed. Concurrently, late after stimulation the nuclear levels of β-catenin were relatively higher than those early after stimulation. Suppression of β-catenin resulted in increased NF-κB activity and interleukin-8 (IL-8) expression in BFT-stimulated cells. However, suppression or enhancement of β-catenin expression neither altered the phosphorylated IκB kinase α/β complex nor activated activator protein 1 signals. Furthermore, inhibition of glycogen synthase kinase 3β was associated with increased β-catenin expression and attenuated NF-κB activity and IL-8 expression in BFT-exposed cells. These findings suggest the negative regulation of NF-κB-mediated inflammatory responses by β-catenin in intestinal epithelial cells stimulated with BFT, resulting in attenuation of acute inflammation in ETBF infection.

Background Time-to-event data of hazard ratios were used to generate a forest plot of all-cause mortality on extracorporeal membrane oxygenation (ECMO) in both overall and individual indications of cardiopulmonary disease in adults. Methods A systemic search was conducted in PubMed from 1975 to 2018. Among 4,121articles, a total of 35 clinical reports comprising 20,610patients (1,631of the patients who underwent ECMO and 18,979of the patients who did not undergo ECMO) met the inclusion criteria. Results The pooled hazard ratio (HR) of 1.2828(95% confidence interval (CI): 0.9649, 1.7054)suggests that the ECMO group was not significantly associated with a reduction in mortality compared with the no-ECMO group in the overall ECMO indications. With respect to the individual indication of respiratory failure as a subgroup analysis, the ECMO group showed significantly improved patient survival, with a pooled HR of 0.6308 (95% CI: 0.5037, 0.7900). Conclusions Most of the included studies are retrospective, which diminishes the significance of the findings due to a higher risk of selection bias, which was exemplified by the allocation of ECMO based on the patients’ severity condition. Greater attention to designing the randomized controlled trials and reporting HRs of ECMO outcomes are needed.

The eradication rates for Helicobacter pylori have decreased in Korea although the prevalence of this bacterium has also decreased. Antibiotic resistance is likely to be a crucial factor in H. pylori eradication success, and we therefore mapped these resistance patterns nationwide in Korea.Five hundred and ninety adult subjects were prospectively enrolled from 2017 to 2018 from 15 centers across six geographic areas of Korea. A total of 580 biopsy tissues had been sampled from these patients during an upper endoscopy and were frozen at -80°C and delivered to a central laboratory. The agar dilution method was used to determine the minimum inhibitory concentration of amoxicillin, clarithromycin, metronidazole, tetracycline, ciprofloxacin, and levofloxacin for each H. pylori isolate.The culture success rate was 60.2% (349/580). Resistance rates against clarithromycin, metronidazole, amoxicillin, tetracycline, levofloxacin, and ciprofloxacin were 17.8%, 29.5%, 9.5%, 0%, 37.0%, and 37.0%, respectively. The geographic distribution of metronidazole and quinolone resistance was highly variable. Some subjects had multiple H. pylori strains in the antrum and body of the stomach and showed a heterogeneous resistance profile between these anatomic areas. The H. pylori multidrug resistance (MDR) rate was 25.2% (88/349) among amoxicillin, clarithromycin, metronidazole, tetracycline, and quinolone and 11.2% (39/349) among four of these major antibiotics except for quinolone. The Seoul and Chungcheong areas showed a relatively lower MDR rate.The antibiotic resistance of H. pylori differs by drug and geographic area in Korea. Detailed nationwide antibiotic resistance mapping is needed to develop an effective H. pylori eradication strategy.

The Bacteroides fragilis enterotoxin (BFT), a virulence factor of enterotoxigenic B. fragilis (ETBF), interacts with intestinal epithelial cells and can provoke signals that induce mucosal inflammation. Although expression of heme oxygenase-1 (HO-1) is associated with regulation of inflammatory responses, little is known about HO-1 induction in ETBF infection. This study was conducted to investigate the effect of BFT on HO-1 expression in intestinal epithelial cells. Stimulation of intestinal epithelial cells with BFT resulted in upregulated expression of HO-1. BFT activated transcription factors such as NF-κB, AP-1, and Nrf2 in intestinal epithelial cells. Upregulation of HO-1 in intestinal epithelial cells was dependent on activated IκB kinase (IKK)–NF-κB signals. However, suppression of Nrf2 or AP-1 signals in intestinal epithelial cells did not result in significant attenuation of BFT-induced HO-1 expression. HO-1 induction via IKK–NF-κB in intestinal epithelial cells was regulated by p38 mitogen-activated protein kinases (MAPKs). Furthermore, suppression of HO-1 activity led to increased apoptosis in BFT-stimulated epithelial cells. These results suggest that a signaling pathway involving p38 MAPK–IKK–NF-κB in intestinal epithelial cells is required for HO-1 induction during exposure to BFT. Following this induction, increased HO-1 expression may regulate the apoptotic process in responses to BFT stimulation.

Helicobacter pylori sheds outer membrane vesicles (OMVs) that contain many surface elements of bacteria. Dendritic cells (DCs) play a major role in directing the nature of adaptive immune responses against H. pylori , and heme oxygenase-1 (HO-1) has been implicated in regulating function of DCs. In addition, HO-1 is important for adaptive immunity and the stress response. Although H. pylori -derived OMVs may contribute to the pathogenesis of H. pylori infection, responses of DCs to OMVs have not been elucidated. In the present study, we investigated the role of H. pylori -derived crude OMVs in modulating the expression of HO-1 in DCs. Exposure of DCs to crude H. pylori OMVs upregulated HO-1 expression. Crude OMVs obtained from a cagA -negative isogenic mutant strain induced less HO-1 expression than OMVs obtained from a wild-type strain. Crude H. pylori OMVs activated signals of transcription factors such as NF-κB, AP-1, and Nrf2. Suppression of NF-κB or Nrf2 resulted in significant attenuation of crude OMV-induced HO-1 expression. Crude OMVs increased the phosphorylation of Akt and downstream target molecules of mammalian target of rapamycin (mTOR), such as S6 kinase 1 (S6K1). Suppression of Akt resulted in inhibition of crude OMV-induced Nrf2-dependent HO-1 expression. Furthermore, suppression of mTOR was associated with inhibition of IκB kinase (IKK), NF-κB, and HO-1 expression in crude OMV-exposed DCs. These results suggest that H. pylori -derived OMVs regulate HO-1 expression through two different pathways in DCs, Akt-Nrf2 and mTOR–IKK–NF-κB signaling. Following this induction, increased HO-1 expression in DCs may modulate inflammatory responses in H. pylori infection.

Background: The increasing prevalence of antimicrobial resistance, together with the lack of novel treatment options, negatively affects successful eradication of Helicobacter pylori. The aim of this study was to investigate genetic mutations in the 23S rRNA genes, which is associated with clarithromycin resistance, and to determine the clinical impact of genotype on phenotypic antimicrobial resistance. Methods: A total of 46 H. pylori strains were obtained from 13 patients, before and after unsuccessful eradication with clarithromycin-based triple therapy. The phenotypic resistance of each H. pylori strain was determined by minimum inhibitory concentration against clarithromycin using the serial two-fold agar dilution method. The genomic sequences of 23S rRNA genes were identified through next-generation sequencing, and nucleotide variants were determined based on comparison with genome sequences of the reference strain H. pylori 26695. Results: Clarithromycin resistance was found in 9 of 13 subjects before treatment and all subjects after unsuccessful eradication. Whole-genome sequencing of the 23S rRNA genes detected 42 mutations on 40 nonidentical loci, including 2147A&gt, G (formerly 2143A&gt, G) and 2146A&gt, G (formerly 2142A&gt, G). All strains with clarithromycin-resistant phenotype had either 2147A&gt, G or 2146A&gt, G mutation. When comparing genotype and phenotype for clarithromycin resistance, there was a significant association between 2147A&gt, G mutation and clarithromycin-resistant phenotype. Conclusions: All clarithromycin-resistant strains had either 2146A&gt, G or 2147A&gt, G mutation, suggesting that tests targeting these two mutations may be enough for the prediction of clarithromycin resistance in this population.

Background and aim Failure of bismuth quadruple therapy for Helicobacter pylori eradication is frequently observed. To increase the eradication rate, comprehensive analyses need to be performed regarding risk factors of bismuth quadruple therapy failure based on complete standard culture and antimicrobial susceptibility testing results. Methods Patients with history of failed first therapy who had H. pylori colonies isolated from culture and successful minimum inhibitory concentration (MIC) test were enrolled. Esomeprazole, bismuth, metronidazole, and tetracycline (quadruple) therapies for 7 or 14 days were given. Eradication rate, treatment compliance, adverse events, and risk factors for the failure of bismuth quadruple therapy were analyzed. Results A total 54 patients were enrolled. Overall eradication rate in the present study was 88.8%. The eradication rate for cases with metronidazole resistance such as MIC 8-16 μg/mL or 16-32 μg/mL was 92.8% (13/14). For cases with high level metronidazole resistance (MIC > 32 μg/mL), the eradication rate was only 60% (6/10). Multivariate analysis regarding compliance, treatment duration, age > 60, three kinds of metronidazole MICs, tetracycline MIC > 4 μg/mL, adverse events and any other parameters, "metronidazole resistance, high level (MIC > 32 μg/mL)" was the only independent risk factor for eradication failure (P = 0.007). Conclusion For cases with metronidazole resistance at MIC > 32 μg/mL, rescue therapy other than bismuth-containing quadruple therapy is needed.

Accurate detection and sensing of bacteria are becoming increasingly important not only in microbiology but in a variety of fields including medicine, food, public health, and environmental science. However, even new rapid methods are not convenient enough. Here, we describe a simple and efficient label-free bacterial detection system using the polydiacetylene (PDA) liposomes immobilized on the 3D polydimethylsiloxane (PDMS) micropillars. Our system utilizes the colorimetric response of amine functionalized PDA vesicles to surfactin, a bacterial cyclic lipopeptide commonly released by Gram-positive Bacillus species as an antibiotic. To improve the sensitivity of PDA vesicles to surfactin by increasing the number and surface area of immobilized vesicles, the PDA vesicles were immobilized on the micropillar structure to give a hierarchical 3D PDA vesicle structure. For the fabrication of the 3D micropillar structure, polydimethylsiloxane (PDMS) was used to overcome the limitations imposed by silicon-based fabrication. In contrast to the 2D-PDA-PDMS system, which could only hardly detect the presence of 500 µM surfactin, the 3D-PDA-PDMS system could efficiently detect the presence of 5 µM surfactin and the initial presence of 4 x 101 cells/ml of Bacillus subtilis NCIB3610, which actively produces surfactin. Furthermore, bacterial strains that are known to produce no surfactin, such as Staphylococcus aureus Newman, Escherichia coli DH5, and Pseudomonas aeruginosa PA14 were not detected by our system suggesting that the 3D-PDA-PDMS system is highly specific to surfactin but not to other chemicals produced by bacteria. Taken together, our results suggest that the 3D-PDA-PDMS system can sensitively and selectively be used for the high throughput detection and screening of biotechnologically important surfactin-producing bacterial strains.

ECMO inevitably increases the risk of infection over time; therefore, lowering infections acquired during ECMO should be further investigated and developed accordingly (Bizzarro,2011). The degree of dysfunction by ECMO is evaluated using several methods, namely: ultrastructural changes in gut epithelium by TEM, plasma lipopolysaccharide (LPS) levels of bacterial products after receiving ECMO, etc. In particular, bacterial lipoteichoic acid (LTA) antigens in plasma can be measured over time by Westernblotlaboratory technique in association with the loss of gut barrier function below. The purpose of this pilot study is to evaluate how newly-developed ECMO reduces infection levels by controlling and stabilizing the overall hemodynamic status, based on the outcome of a Westernblot.

We know little concerning the expression of transforming growth factor-β1 (TGF-β1) and TGF-β1-induced epithelial-mesenchymal transition (EMT) markers in gastric mucosa and their changes after eradication of Helicobacter pylori infection have not yet been clarified. In the present study, we compared the time course of messenger RNA (mRNA) expression of TGF-β1 and five EMT markers (Twist, Snail, Slug, vimentin and E-cadherin) in 111 controls, 55 patients with gastric dysplasia and 71 patients with early gastric cancer, following eradication of H.pylori. mRNA levels in non-cancerous gastric mucosa were measured using quantitative real time-polymerase chain reaction and the histologic findings of gastric mucosa were compared before and after eradication. The average duration of follow-up was 46.7 months (6.0-112.4). The levels of TGF-β1, Twist, Snail, Slug and vimentin mRNA, in addition to levels of CD44 detected by immunohistochemistry, showed all up-regulation in patients with dysplasia or early gastric cancer compared with controls (P < 0.05); moreover, the mRNA levels of E-cadherin, an epithelial marker, were decreased in these patients compared with the control group (P < 0.001). Eradication of H.pylori reduced the expression of TGF-β1, Twist, Snail, Slug and vimentin mRNA (P-value for slope

IMPORTANCE: This review provides a comprehensive comparison of treatment outcomes between robot-assisted laparoscopic surgery (RLS) and conventional laparoscopic surgery (CLS) based on randomly-controlled trials (RCTs). OBJECTIVES: We employed RCTs to provide a systematic review that will enable the relevant community to weigh the effectiveness and efficacy of surgical robotics in controversial fields on surgical procedures both overall and on each individual surgical procedure. EVIDENCE REVIEW: A search was conducted for RCTs in PubMed, EMBASE, and Cochrane databases from 1981 to 2016. Among a total of 1,517 articles, 27 clinical reports with a mean sample size of 65 patients per report (32.7 patients who underwent RLS and 32.5 who underwent CLS), met the inclusion criteria. FINDINGS: CLS shows significant advantages in total operative time, net operative time, total complication rate, and operative cost (p < 0.05 in all cases), whereas the estimated blood loss was less in RLS (p < 0.05). As subgroup analyses, conversion rate on colectomy and length of hospital stay on hysterectomy statistically favors RLS (p < 0.05). CONCLUSIONS: Despite higher operative cost, RLS does not result in statistically better treatment outcomes, with the exception of lower estimated blood loss. Operative time and total complication rate are significantly more favorable with CLS. More RCT evidence is needed to be accumulated in order to enable full subgroup analyses on each surgical procedure.

Background Carbapenemase-producing Enterobacteriaceae (CPE) can lead to life-threatening outcomes with rapid spread of the carbapenemase gene in solid organ transplantation (SOT) recipients because of limitations of available antibiotics. We examined the characteristics and importance of CPE acquisition in SOT recipients with large numbers of CPE isolates. Methods Between November 2015 and October 2016, 584 CPE isolates were found in 37 recipients and verified by carbapenemase gene multiplex polymerase chain reaction (PCR). One hundred recipients with at least 2 negative results in carbapenemase PCR for stool surveillance and no CPE isolates in clinical samples were retrospectively included. Results Most CPE isolates were Klebsiella pneumoniae carbapenemase (KPC)-producing K. pneumoniae (546, 93.5%). The most frequent transplantation organ was lung (43.3%), and the most common sample with CPE isolates other than stool was respiratory tract (22.6%). The median time between SOT and first CPE acquisition was 7 days. All-cause mortality was significantly higher in recipients with CPE than in those without CPE (24.3% vs 10.0%; P = .03). In multivariate regression analysis, stool colonization of vancomycin-resistant Enterococci and/or Clostridium difficile during 30 days before SOT (odds ratio [OR], 3.28; 95% CI, 1.24–8.68; P = .02), lung transplantation (OR, 4.50; 95% CI, 1.19–17.03; P = .03), and intensive care unit stay ≥2 weeks (OR, 6.21; 95% CI, 1.72–22.45; P = .005) were associated with acquisition of CPE. Conclusions Early posttransplantation CPE acquisition may affect the clinical outcome of SOT recipients. Careful screening for CPE during the early posttransplantation period would be meaningful in recipients with risk factors.

Background Amoxicillin (Amx) is one of the most important antibiotics for eradication of Helicobacter pylori (H. pylori). Main determinants of genetically stable Amx resistance are mutations in the C-terminus of penicillin-binding protein 1A (pbp1A). However, contribution of individual mutation remains unclear. Methods 77 Amx-resistant (AmxR) and 77 Amx-susceptible (AmxS) H. pylori strains were isolated from gastric tissues, and DNA sequencing was performed to compare C-terminus sequences of pbp1A gene between AmxR and AmxS strains. Natural transformation of these mutated genes into amoxicillin-susceptible strains was performed. Results Among many mutations in pbp1A, D479E (OR: 37.4, 95% CI: 5.53-252.49, P

Bacteroides fragilis enterotoxin (BFT), a virulence factor of enterotoxigenic B. fragilis (ETBF), plays an essential role in mucosal inflammation. Although autophagy contributes to the pathogenesis of diverse infectious diseases, little is known about autophagy in ETBF infection. This study was conducted to investigate the role of BFT in the autophagic process in endothelial cells (ECs). Stimulation of human umbilical vein ECs (HUVECs) with BFT increased light chain 3 protein II (LC3-II) conversion from LC3-I and protein expression of p62, Atg5, and Atg12. In addition, BFT-exposed ECs showed increased indices of autophagosomal fusion with lysosomes such as LC3–lysosome-associated protein 2 (LAMP2) colocalization and the percentage of red vesicles monitored by the expression of dual-tagged LC3B. BFT also upregulated expression of C/EBP homologous protein (CHOP), and inhibition of CHOP significantly increased indices of autophagosomal fusion with lysosomes. BFT activated an AP-1 transcription factor, in which suppression of AP-1 activity significantly downregulated CHOP and augmented autophagosomal fusion with lysosomes. Furthermore, suppression of Jun N-terminal protein kinase (JNK) mitogen-activated protein kinase (MAPK) significantly inhibited the AP-1 and CHOP signals, leading to an increase in autophagosomal fusion with lysosomes in BFT-stimulated ECs. These results suggest that BFT induced accumulation of autophagosomes in ECs, but activation of a signaling pathway involving JNK, AP-1, and CHOP may interfere with complete autophagy.

rdxA and frxA mutations and enhancement of efflux pump have been suggested as the cause of metronidazole resistance in Helicobacter pylori. This study was performed to investigate the resistance mechanisms related to clinical eradication outcome, and to examine direct involvement of hefA in metronidazole-resistant isolates with intact rdxA and frxA.A total of 53 H. pylori-positive patients who were treated with metronidazole-containing sequential or quadruple therapy from 2011 to 2015 were enrolled. The metronidazole susceptibility of H. pylori isolates was examined by agar dilution test. Mutations in rdxA and frxA, were analyzed with DNA sequencing, and impact of hefA on metronidazole resistance was examined with quantitative real-time reverse transcription polymerase chain reaction, knockout and genetic complementation test for hefA.Seven mutation types of rdxA and/or frxA were found in H. pylori isolated from non-eradicated subjects. rdxA mutation was associated with eradication failure (P = 0.002), and nonsense mutation in rdxA reduced eradication efficacy (P = 0.009). hefA expression was significantly higher in resistant isolates (P 0.001), especially in rdxA(-)frxA(-) as compared to rdxA(+)frxA(+) (P = 0.027). Resistant isolates with no mutation in rdxA and frxA became susceptible after hefA knockout. Genetic complementation for hefA recovered metronidazole resistance in all of three hefA knockout mutants.These results suggest that rdxA mutations play a critical role in metronidazole resistance as well as the outcomes of eradication therapy. In addition, hefA seems to be directly involved in metronidazole resistance, which explains the resistance in clinical isolates with intact rdxA and frxA.

Background and Aim Dendritic cells (DCs) are observed on the Helicobacter pylori-infected gastric mucosa. DCs generally play an important role in the regulation of inflammation. Although stimulation of gastric epithelial cells with H. pylori vacuolating cytotoxin (VacA) has been reported to induce apoptosis and endoplasmic reticulum (ER) stress, the effects of VacA on the DC apoptotic response have not been well elucidated. This study was conducted to investigate the role of H. pylori VacA on the apoptotic process and ER stress in DCs. Methods Murine and human DCs were generated from specific pathogen-free C57BL/6 mice and human peripheral blood mononuclear cells, respectively. DCs were incubated with purified VacA, after which Bax activation, cytochrome c release, and DNA fragmentation for apoptosis were measured by fluorescent microscopy, immunoblot, and ELISA. ER stress-related molecules such as GRP78 and CHOP were analyzed by immunoblot. Results Treatment of DCs with purified H. pylori VacA resulted in the induction of apoptosis. DC stimulation with VacA led to the translocation of cytoplasmic Bax to mitochondria and cytochrome c release from mitochondria. H. pylori VacA induced signals for ER stress early during the stimulation process in DCs. Furthermore, suppression of ER stress resulted in a significant inhibition of the VacA-induced apoptosis in DCs. Conclusion These results suggest that ER stress is critical for regulation of DC apoptotic process in response to VacA stimulation.

Background and Aim Clinical outcomes of Helicobacter pylori (HP) infection have been shown to be dependent on the variability of virulence factors. The aim of this study was to evaluate the prevalence of each virulence factor and the association between polymorphisms of the virulence factors of HP, and the clinical outcome of gastroduodenal diseases in South Korea. Methods Four hundred one HP colonies were analyzed (75 colonies from 45 controls; 71 colonies from 39 benign gastric ulcer [BGU] patients; 102 colonies from 54 duodenal ulcer [DU] patients; 121 colonies from 77 stomach cancer patients; and 32 colonies from 25 dysplasia patients). Polymerase chain reaction amplifications for vacA, cagA, iceA, oipA, and dupA were performed using DNA extract from HP isolates cultured from mucosal biopsy specimens. dupA was regarded as positive when all of jph0718, jph0719, and dupA were positive. Results Most colonies were composed of vacA s1 (100.0%), i1 (100.0%) and m1 (92.9%), cagA-positive (87.2%), iceA1 (95.8%), oipA-positive (91.2%), and dupA-negative (52.0%) genotypes. dupA was more frequently expressed in BGU (81.3%), DU (74.7%), and dysplasia (41.7%) than control (16.7%) (P

Background and Aim The aim of this study is to evaluate the effect of metformin on intestinal inflammation. Methods COLO205 cells were pretreated with metformin and stimulated with tumor necrosis factor (TNF)-α. Expression of interleukin (IL)-8 was determined by luciferase assay and real-time PCR. Inhibitor of kappaB (IκB) phosphorylation/degradation and adenosine monohosphate-activated protein kinase (AMPK) activity were evaluated by Western blotting. DNA-binding activity of transcription factor nuclear factor-kappaB (NF-κB) was assessed by electrophoretic mobility shift assay. In an acute colitis model, mice were given 4% dextran sulfate sodium (DSS) for 5 days. IL-10−/− mice were used to evaluate the effect of metformin on chronic colitis. In an inflamation-associated tumor model, mice were given a single intraperitoneal injection of azoxymethane followed by three cycles of 2% DSS for 5 days and 2 weeks of free water consumption. Results Metformin significantly inhibited IL-8 induction in COLO 205 cells stimulated with TNF-α. Metformin attenuated IκBα phosphorylation and NF-κB DNA-binding activity. Administration of metformin significantly reduced the severity of DSS-induced colitis. In addition, DSS-induced IκB kinase (IKK) activation was significantly reduced in mice treated with metformin. Metformin significantly attenuated the severity of colitis in IL-10−/− mice, induced AMPK activity in intestinal epithelial cells, and inhibited the development of colitic cancer in mice. Conclusions These results indicate that metformin suppresses NF-κB activation in intestinal epithelial cells and ameliorates murine colitis and colitis-associated tumorigenesis in mice, suggesting that metformin could be a potential therapeutic agent for the treatment of inflammatory bowel disease.

Background/Aims Helicobacter pylori infection induces cyclooxygenase-2 (COX-2) and epidermal growth factor receptor (EGFR) overexpression, and these factors may engage in cross-talk. The aim of the present study was to evaluate the effect of H. pylori on EGFR signaling pathways and to determine whether celecoxib has an inhibitory effect on this pathway. Methods The AGS cell line was cocultured with H. pylori G27 and the isogenic cagE- mutant. The expression of COX-2, EGFR, heparin binding-epidermal growth factor (HB-EGF), and transforming growth factor-β (TGF-β) was measured by real time-polymerase chain reaction (RT-PCR). Next, Western blot analyses of COX-2, EGFR, total Akt, phosphorylated Akt (pAkt), and phosphorylated glycogen synthase kinase-3β (pGSK3β) were performed after incubating H. pylori-treated AGS cells for 24 hours with various concentrations of celecoxib (0, 10, 20, and 30 µmol/L). Results H. pylori infection upregulated the mRNA levels of COX-2, EGFR, HB-EGF, and TGF-β, as detected by RT-PCR. However, AGS cells treated with cagE- mutants, which have a defective type IV secretion system, did not exhibit EGFR upregulation. Celecoxib had inhibitory effects on the H. pylori-induced overexpression of COX-2 (p=0.015), EGFR (p=0.025), pAkt (p=0.025), and pGSK3β (p=0.029) by Western blot analysis. Conclusions H. pylori with an intact type IV secretion system activated the COX-2 and EGFR-Akt pathways in the AGS cell line. As celecoxib exhibited inhibitory effects on the EGFR signaling pathway, the cross-talk of COX-2 and EGFR likely mediates H. pylori-induced gastric cancer.

Changes of DNA methylation in gastric mucosae after eradication of Helicobacter pylori have not been clarified yet. From this background, we investigated time course of DNA methylation following H. pylori eradication in 221 successfully H. pylori eradicated subjects with endoscopic follow-up at least for 6 months, including 114 controls, 53 subjects with gastric dysplasia and 54 patients with early gastric cancer. All dysplasia and gastric cancer patients underwent endoscopic resection at the time of enrollment. The methylation levels in LOX, APC and MOS genes from noncancerous gastric mucosae using quantitative methylation-specific PCR, as well as the histologic findings of gastric mucosae, were compared before and after eradication. Average follow-up duration was 26.0 months (range: 6 to 76 months). H. pylori eradication decreased methylation levels in LOX (p-value for slope

To investigate whether the phenyl-thiophenyl propenone RK-I-123 suppresses interleukin-8 (IL-8) expression and activation of mitogen-activated protein kinases (MAPKs) and transcription factors (nuclear factor-κB [NF-κB] and activator protein-1 [AP-1]) by reducing reactive oxygen species (ROS) levels in Helicobacter pylori-infected gastric epithelial cells. Helicobacter pylori in Korean isolates, human gastric epithelial AGS cells. AGS cells pretreated with or without RK-I-123 were cultured in the presence of H. pylori at a bacterium/cell ratio of 300:1. Reactive oxygen species and IL-8 levels were determined by dichlorofluorescein fluorescence and enzyme-linked immunosorbent assay. The IL-8 mRNA expression was analyzed by the real-time reverse transcription-polymerase chain reaction (RT-PCR). The MAPK and IκBα levels were determined by western blotting. The activation of NF-κB and AP-1 was determined by the electrophoretic mobility shift assay. Helicobacter pylori induced an increase in ROS and IL-8 expression and activation of MAPKs and transcription factors (NF-κB and AP-1) together with the degradation of IκBα in AGS cells, all of which were inhibited by RK-I-123. The RK-I-123 suppressed the H. pylori-induced IL-8 expression and activation of MAPKs, NF-κB, and AP-1 by reducing ROS levels in AGS cells. The RK-I-123 may be a potential candidate for the treatment of H. pylori-induced gastric inflammation.